An adaptive energy management strategy for supercapacitor supported solar-powered electric vehicle charging station

Abstract

Abstract Large-scale electric vehicle integration into the grid is expected in the imminent future. Congestion caused by these integrations can be addressed through a hybrid AC/DC microgrid. The DC sub-grid is exclusively dedicated to incorporating electric vehicles. Solar-powered charging station supported with a supercapacitor energy storage system in the DC sub-grid reduces the stress on the AC sub-grid. This paper presents a hybrid AC/DC microgrid voltage/frequency stability improvement strategy based on adaptive DC-link voltage regulation assisted by energy storage. The proposed volatility-based approach is an efficient strategy to enhance the microgrid stability during generation intermittency and load fluctuations. The combined control scheme of the interlinking converter and supercapacitor energy storage in the independent and hybrid operation modes achieve energy balance with the variations in solar irradiation and the addition/disconnection of electric vehicles. The proposed energy management strategy is tested in real-time under various volatile conditions to validate the performance. The hybrid microgrid with proposed energy management strategy provided a frequency improvement of 0.55% and voltage improvement of 5.4%.